Synthesis
DOI: 10.1055/s-0041-1737816
special topic
Bürgenstock Special Section 2021 – Future Stars in Organic Chemistry

Generation of Thiyl Radicals from Air-Stable, Odorless Thiophenol Surrogates: Application to Visible-Light-Promoted C–S Cross-Coupling

Charlie Swan
,
Lorenzo Maggi
,
Mahri Park
,
Sophie Taylor
,
William Shepherd
,
Liam T. Ball
This work was supported by the Engineering and Physical Sciences Research Council (EPSRC) Centre for Doctoral Training in Sustainable Chemistry (EP/S022236/1) through a Ph.D. studentship to C.S., and a UKRI Future Leaders Fellowship to L.T.B. (MR/V022067/1).


Abstract

The synthetic versatility of thiophenols is offset by their air-sensitivity and foul odor. It is demonstrated that S-aryl isothiouronium salts can be used as precursors to thiyl radicals, extending the practical benefits of these air-stable, odorless salts from ionic to single electron manifolds. The isothiouronium salts are accessed via Ni-catalyzed cross-coupling of (hetero)aryl iodides and thiourea and are isolated as free-flowing solids following anion exchange. Judicious choice of a redox-innocent counteranion enables use of these convenient thiophenol surrogates in radical processes, as is exemplified by the synthesis of non-symmetrical diaryl thioethers via light-promoted S-arylation.

Supporting Information



Publication History

Received: 13 October 2021

Accepted after revision: 10 January 2022

Publication Date:
10 February 2022 (online)

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